(a) Field of the Invention
The present invention relates to an apparatus, a system and a method for controlling engine starting while shifting of a hybrid electric vehicle. More particularly, the present invention relates to an apparatus, a system and a method for controlling engine starting while shifting of the hybrid electric vehicle that minimizes a fuel consumption amount of the engine by determining an engine starting time when a current operating state of the hybrid electric vehicle requests a kick down shift required to start the engine and coupling of the engine clutch.
(b) Description of the Related Art
Generally, a hybrid electric vehicle is driven by a combination of an engine which generates torque from fuel combustion and an electric motor which generates torque from an electric battery. Hybrid electric vehicles are typically provided with optimum output torque, depending on how the engine and the motor are operated while the vehicles are driven by the two power sources (i.e., engine and the motor).
In hybrid electric vehicles, a transmission mounted electric device (TMED) type of power train in which an engine clutch is disposed between the engine and the motor is generally used. Thus, the hybrid electric vehicle is driven in an EV mode or an HEV mode in accordance with connection of the engine clutch.
In the TMED type of the hybrid electric vehicle, when a demand torque of a driver is increased suddenly (e.g., a kick down shift is requested) in order to accelerate in the EV mode, the hybrid electric vehicle performs a kick down shift control that shifts the vehicle into a lower gear.
While kick down shift controlling, it is desirable that the engine clutch of the hybrid electric vehicle be coupled while simultaneously shifting. The engine clutch, to however, is coupled before shifting or after shifting because of control complexity. Do to this; drivers are often not satisfied with the acceleration output from hybrid electric vehicles.
The control for coupling the engine clutch of the TMED type of the hybrid electric vehicle in a real shifting region is essential for proper acceleration. Therefore, determination of the engine starting time for coupling the engine clutch is important to providing a responsive hybrid electric vehicle.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.